基于流-固耦合的混合火箭发动机固体燃料表面退移速率计算

Regression rate calculation for the solid fuel surface of hybrid rocket motor based on fluid-solid coupling technique

基于流-固耦合的方法,在充分考虑混合火箭发动机工作过程中诸多复杂物理过程的基础上,建立了一个可适用于不同工作状况下混合火箭发动机固体燃料表面退移速率预示的计算模型。计算结果与实验数据的对比验证了所建立计算模型的准确性。对模型发动机进行模拟的结果表明,混合火箭发动机中的燃烧、流动及固体燃料表面的退移速率具有明显的不均匀性,发动机中的固体燃料表面的退移速率沿轴向近似地呈“W”形状的曲线变化;在混合发动机中,突扩形状的预燃室和补燃室有利于燃料热解气体和氧化剂气体的扩散混合,可以强化对固体燃料表面的换热,提高固体燃为表面的退移速率。

Based on the fluid-solid coupling technique and some comprehensive physical processes during working of hybrid rocket motor, a numerical model was developed to predict the regression rate for the solid fuel surface of hybrid rocket motor under different working conditions. Accuracy of the calculated model was verified by comparison of calculation results with experiment data. The simulation results of model motor show that combustion ,flow and regression rate of solid fuel surface of hybrid rocket motor are of inhomogeneity, and regression rate change curve along axial direction fits a ＂W＂ figure approximatively;prechamber and secondary chamber with sudden-expending shape are favorable to diffusion mix of pyrolysis gas of fuel with oxidant, intensifying heat transfer of solid fuel and improving the regression rate of solid fuel surface.